Strap dispenser



July 22, 1958 R. c. LUTH 2,844,334

,STRAP DISPENSER Filed May 4, 1955 2 Sheets-Sheet 1 INVENTOR:

y 2 958 v R. c. LUTH 2,844,334

STRAP DISPENSER Filed May 4, 1955 v 2 Sheets-Sheet 2 u v III/I4VIII/[III]IIIIIIlIIIII/lfiUIIIIIIId/IIL- A IIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIIIIIIIIA IN V EN TOR.

, aze- United States Patent STRAP DISPENSER Robert C. Luth, Chicago, IlL, assignor to Signode Steel Strapping Company, Chicago, Ill., a corporation of Delaware Application May 4, 1955, Serial No. 505,945

11 Claims. (Cl. 242-128) The present invention relates to a new and improved strap dispenser, particularly a dispenser in which strap is supplied from a mill wound coil.

Strap for binding packages, boxes, bundles, coils of wire or tubing, and the like, is supplied from the finishing mill in coils described as mill wound and ribbon wound. A mill wound coil is one having a thickness greater than the strap Width, usually three to six times as thick, and wherein the strap convolutions crisscross so that the strap is evenly distributed throughout the coil. A ribbon wound coil has a thickness equal to the width of the strap, and each convolution exactly overlies the next.

From the manufacturing and original handling standpoint, mill wound coils have advantages over ribbon wound coils. In the first place it is relatively easy to produce a mill wound coil with the strap distributed relatively evenly throughout by means of a tracing finger guiding the strap onto the takeup reel as the coil is wound. Secondly, for any given diameter a mill wound coil will have many times as much strap in it as a ribbon wound coil, and thus coils of excessively large diameter are avoided.

On the other hand, mill wound coils have some disadvantages, particularly when they are desired for use with power strapping machines. It has been found that the inertia of such coils, particularly when they are fresh and have relatively great weight, produces a great shock on the strap feeding mechanism of the strapping machine. The crosslays or crisscrossing of the strap convolutions create a tendency of the strapping to snag as it is withdrawn from the coil. Another possibility is that rotational inertia will cause such coils to overrun When the' feed to the machine has been terminated. This overrunning leaves a substantial length of strap lying loose between the coil and the feeding mechanism of the strapping machine, which increases the opportunity for snagging.

With the nousnagging strap dispenser of the present invention, a mill wound coil is first slowly transformed into a ribbon wound coil of relatively few turns or convolutions from the center of which the strap is withdrawn by the user which is usually a power strapping machine. With this arrangement the possibilities of snagging are eliminated because the strap is paid off from the center of the mill Wound coil which has no crosslays. The resistance to pull factor is controlled since the mill wound coil is free to skid, and there is a gradual acceleration of the coils and the reel, thus eliminating starting shock and jerking. I

It is, therefore, an object of the present invention to provide a new and improved nonsagging strap dispenser wherein a mill wound coil is first converted into a ribbon wound coil of relatively few turns or convolutions, and the strap is withdrawn for use from the center of the ribbon wound coil, the ribbon wound coil being built up and the mill wound coil being exhausted as the strapping is withdrawn from the dispenser.

And

Another object is to provide a new and improved nonsnagging strap dispenser which has substantially no resistance load to be overcome by the mechanism pulling the strap from the coil.

Another object is to provide a new and improved nonsagging dispenser which produces a ribbon wound coil at the center of the mill wound coil and the strap is withdrawn from the center of the ribbon wound coil.

Another object is to provide a new and improved strap dispenser wherein the overrunning of the dispenser is accompanied by loosening the convolutions in the ribbon wound coil which has been formed.

Another object is to provide an improved nonsagging strap dispenser into which a mill wound coil may be easily loaded in a minimum amount of time.

Another object is to provide a new and improved nonsagging strap dispenser which has relatively few parts and will work satisfactorily for a substantial length of time without servicing or repairs.

Other objects and advantages will become apparent from the following description taken in conjunction with the accompanying drawings, wherein:

Fig. 1 is a plan view of the nonsagging strap dispenser forming the subject matter of the present invention;

Fig. 2 is an irregular sectional view, taken substantially along the line 22 of Fig. 1, looking in the direction of the arrows, showing the mill wound coil as indicated in section, and the ribbon wound coil and the stripping mechanism in elevation;

Fig. 3 is an enlarged cross sectional view, taken substantially along the irregular line 33 of Fig. 1, looking in the direction of the arrows, illustrating the mounting and the means for forming the ribbon wound coil and for guiding strap down therefrom;

Fig. 4 is a fragmentary perspective view of a portion of the stripping mechanism, showing the guiding and wear block at the exit from the coil; and

Fig. 5 is a view similar to Fig. 3, and showing a modified construction of the nonsagging strap dispenser of this invention.

In the drawings, the dispenser 10 includes a reel 12, a mounting 14, and means 16 for stripping the strap from the center of a ribbon wound coil.

The mounting comprises a stand or base 18 having flanges 20 formed with apertures 22 through which mounting bolts or screws may be inserted. The stand or base 18 includes an upstanding bearing hub 24 on which is mounted a thrust bearing 26 of conventional construction,

the inner race 28 of which is supported on an annular shoulder 30 on the hub 24.

The reel 12 includes a reel plate 32 to which is secured, as by welding, an upstanding flange or circular Wall 34 adjacent the periphery thereof, as best shown in Fig. 2. At its center the reel plate 32 is formed with a circular aperture 36 to receive the bearing 26, and the reel is supported on the bearing 26 by a housing 38 having a shoulder 40 bearing on the outer race 42 of the thrust bearing 26. The bearing housing 38 is secured to the reel plate 32 by a plurality of bolts 44 extending through suitable apertures in the plate 32 and into tapped openings in the bearing housing 38.

, rotate on the hub 24 about an axis perpendicular to the It is thus clear that the reel 12 may 3 behind the reel plate 32 at the locus of the ribbon wound coilRS.

The reel 12 also includes a core plate or center disc 46 having an outer diameter substantially less than the diameter of the reel plate 32, and which is adapted to be secured to the reel plate 32 by the bolts 44 which pass through openings 48' formed in the center disc 46. The center disc 46 has a central aperture 47 which is the same size as the reel plate aperture 36 and accommodates the bearing26.

The stripping means 16 includes a generally circular stripper plate 50" which is secured to the upper face of the hub 24 by a bolt 52 which is screwed into a tapped opening 54 inthe hub. The stripper plate is restrained against rotational movement by a locating pin 56 extending through an opening in the plate 50 and into a bore in the hub 24.

The stripper plate 50 is' formed with a peripheral arcuate slot or recess 58 which subtends an angle of approximately 60 degrees and the inner arcuate edge 59 of which has a radius slightly less than that of the center disc 46 (Fig. 1). At one end of the recess 58 is a wear and guide block 60 having a slot 62 at one side thereof to receive the radial straight end edge 64 of the arcuate recess 58.

Adjacent the ercuate edge so of the recess 58 the guide block 60 is formed with a notch 66 which guides the strap S to the device, machine, or the like, which is pulling the strap from the dispenser. The strap passes over a second guide and wear block 68 shaped similarly to the block 60, and secured to the radial straight edge of the recess 58 at the end thereof opposite the block 60. Thus, strap S passes under the guide block 60 and over the wear block 68.

Additional retardation to prevent overrunning of the reel and coils may be supplied by a drag brake 70 having a brake member 72 biased against the underface 74 of the reel plate 32. This brake 70 may be of any conventional construction and preferably is of the type where the pressure of the shoe 72 against the reel plate 32 may be regulated in order to produce a proper amount of drag. The brake 70 might also be of the release type which would be manually or automatically released when strap is pulled from the reel. And in some. instances no brake would be needed or used.

A mill wound coil MS is loaded into an empty dispenser 10 by dropping it down into the reel 12 and disposing it around the stripper plate 50. The restraining means, strapping or wire, binding the mill wound coil is removed and a length of strap S is taken from the center of the coil MS and passed completely around the center disc 46 and the end is drawn out under the block 60, through the guiding slot 66, over the wear block 68, and threaded through the strapping machine or equipment which is to use the strap. As strap is drawn from the dispenser 10, acoil RS of ribbon wound strap will build up around the center disc 46. Because the ribbon wound coil RS initially is loose and may skid on the reel plate 32, this coil will build up to several convolutions by depleting the mill wound coil MS, and without rotating the reel 12. When sufiicient friction is developed between the ribbon wound coil RS and the reel plate 32 and the center disc 46, further withdrawal of the strap S from the dispenser will rotate the reel 12 with gradual acceleration, and temporarily there may be no transfer of strap from the mill wound coil to the ribbon wound coil. falls below the amount necessary to drive the reel and coils, the reel will cease rotation and the ribbon Wound coil RS will build up at the expense of the mill wound coil MS. This will continue with the ribbon wound coil RS being alternately built up and partially depleted until the mill wound coil MS is exhausted.

This dispenser utilizes the inherent friction in the assembly, plus that of the brake 70 when used, and the weight of the strapping in its proper functioning. At the outset of using, a freshmill wound coil, a length of strap- When this friction ping is passed around the center disc as previously described, and is fed to the strapping machine. For a short While the strapping machine will take strap from the center of the ribbon wound coil with the reel stationary, and the number of convo'lutions in the ribbon wound coil will increase with its outer diameter smaller than the inner diameter of the mill wound coil. During this time the ribbon wound coil skids on the reel plate 32. As the number of turns in the ribbon wound coil RS increases, its friction on the reel plate 32 and against the center disc 46 increases, and when it is great enough to overcome the frictional and other forces retarding the reel, withdrawal of strapping from the center of the ribbon wound coil RS will rotate the reel and the coils, and temporary buildup of the ribbon wound coil will cease.

From the foregoing it should be clear that the reel plate 32 need not be horizontal, but if it is turned to a position where gravity would not cause the ribbon wound coil RS to press against the reel plate 32 with enough force to produce' the required friction at the ribbon wound coil, external means such as the previously mentioned magnets can be used.

The number of turns in the ribbon wound coil RS will depend upon varying factors. First of all, the number of.

turns will be greater when the mill wound coil is full, and less when it is empty, because the forces resisting rotation include the weight of the coils. Strapping of narrow width, such as inch, will build up a ribbon wound coil of more convolutions than strapping of widths in the order of inch, for example, because friction is a function of weight and the narrower strapping produces lighter ribbon wound coils. Another factor is the type of strapping which is used. A slick surfaced strapping will have more turns in the ribbon wound coil RS because it will produce less friction than the conventional rust protection finished strapping. However, it might be stated that the ribbon wound coil will have ten or more convolutions during normal operation of the dispenser 12.

In Fig. 5a modification of the dispenser has been shown and in which, in so far as possible, similar numbers are used to designate the same or similar parts. In this mod-ifi'cation the ribbon wound coil RS is built up about a center disc 80 which is not locked to the reel disc 32, but which may turn relative thereto. It is mounted for rotation about a bearing housing 84 which has an annular recess 86 to receive the inner edge 88 of the disc, the bearing housing 84 being secured to the reel disc 32 by suitable studs 90. The bearing housing 84 has an inner shoulder 92 which overlies the outer race 42 of the thrust bear-ing26 to support the reel 12.

If additional friction is required between the center disc 80' and the upper surface of the reel plate 32, a thin sheet 94 of rubber, which is preferably one-eighth of an inch thick, may be inserted therebetween and adhered to the reel plate in some suitable manner, as by vulcanizing, cementing, or the like. If it is not desired, or feasible, to use the rubber sheet 94, a generous layer of rubber coating may be adhered to the underside of the center disc 80. The rubber sheet 94 may also be extended to the outer edge of the reel to add to the friction between the ribbon wound coil RS and the reel plate 32.

In this modification the ribbon wound coil RS will be built up about the center disc 80 in the same manner as about the center disc 46. However, since the center disc 80 is capable of movement relative to the reel plate 32, substantially more turns of ribbon wound coil will be built up before there is suflicient friction developed structed and operated in the same fashion as the modification shown in Figs. 1 to 4, and is provided with the stripper plate 50 and the upper and lower wear blocks 60 and 68. I

It will be seen from the foregoing specification that the objectives which were claimed for this invention at the outset have been attained and that a newand improved nonsnagging strap dispenser has been developed.

While two embodiments of the strap dispenser constituting this invention have been shown and described, it will be apparent that modifications and variations thereof may be made without departing from the underlying principles of the invention. It is, therefore, desired by the following claims to include within the scope of the invention all such variations and modifications by which substantially the results of this invention may be obtained through the use of substantially the same or equivalent means. 7

What is claimed as new and desired to be secured by United States Letters Patent is:

1. A strap dispenser including in combination means supported for rotation and adapted to support a mill wound coil of strap with its axis generally parallel to the axis of rotation of said means, means supported by and rotatable with said coil supporting means and about which a coil of ribbon wound strap may be formed which also is adapted to be supported by said coil supporting means, the withdrawal of strap from the center of said ribbon Wound coil rotating said coil supporting means when the friction between the ribbon wound coil and said coil supporting means and said last named means is suflicient to overcome the forces resisting rotation of said coil supporting means and the coils.

2. A strap dispenser including in combination means supported for rotation and adapted to support a mill wound coil of strap with its axis generally parallel to the axis of rotation of said means, and circular means on said coil supporting means and rotatable about the axis of rotation of said coil supporting means and about which a ribbon wound coil of strap may be formed from the center of the mill Wound coil, withdrawal of strap from the center of the ribbon wound coil being adapted to rotate said supporting means when the friction between the ribbon wound coil and said supporting and circular means is sufficient to overcome the forces resisting rotation of said supporting means and the coils.

3. A strap dispenser including in combination means supported for rotation and adapted to support a mill wound coil of strap with its axis generally parallel to the axis of rotation of said means, circular means on and rotatable about the axis of rotation of said coil supporting means about which a ribbon wound coil of strap may be formed from the center of the mill wound coil, withdrawal of strap from the center of the ribbon wound coil being adapted to rotate said supporting means when the friction between said circular and supporting means and the ribbon wound coil is sufficient to overcome the forces resisting rotation of said supporting means and the coils, and a stationary stripper mechanism associated with said means to guide strap pulled from the center of the ribbon wound coil.

4. A strap dispenser including in combination a reel adapted to support a coil of mill wound strap, means mounting said reel for rotation, a stripper mechanism positioned adjacent said reel and spaced therefrom a distance only slightly greater than the width of the strap in the coil, and means positioned between said reel and said stripper mechanism and about which strap is adapted to be wound in ribbon wound coil form, said last named means being mounted for rotation about the axis of rotation of said reel, whereby strap is Wound about said last named means from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use, withdrawal of strap from the center of the ribbon wound coil rotating said reel 6 when the friction developed between the ribbon wound coil and said reel and said last named means is sufficient to overcome the forces resisting rotation.

5. A strap dispenser including in combination a reel adapted to support a coil of mill wound strap, means mounting said reel for rotation, a stationary stripper mechanism associated with and spaced from said reel a distance only slightly greater than the width of the strap in the coil, a center disc having a driving connection with and positioned between said reel and said stripper mechanism and about which strap is adapted to be wound in ribbon Wound coil form, and said stripper mechanism including means to guide the strap as it is withdrawn from a convolution adjacent the periphery of said center disc, whereby strap is wound about said center disc from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use, the withdrawal of strap from the center of the ribbon wound coil rotating said reel and the coils when the friction developed between the ribbon wound coil and said reel and said center disc is sufficient to overcome the forces resisting rotation.

6. A strap dispenser including in combination a generally horizontallydisposed reel adapted to support a coil of mill wound strap with its axis generally vertical, means mounting said reel for rotation about a generally vertical axis, a stationary stripper plate mounted on said mounting means and positioned above said reel a distance only slightly greater than the width of the strap in the coil, a center disc having a driving connection with said reel and positioned between said reel and said stripper plate and about which strap is adapted to be wound in ribbon wound coil form, and guiding means on said stripper plate including a recess in the periphery thereof and guiding elements associated therewith to guide the strap as it is withdrawn from a convolution at the center of the ribbon wound coil and adjacent the periphery of said center disc, whereby strap is wound about said center disc from the center of the mill wound coil to form a-ribbon wound coil from the center of which strap is pulled for use, the withdrawal of strap from the center of the ribbon wound coil rotating said reel and the coils when the friction developed between the ribbon wound coil and said reel and said center disc is sufiicient to overcome the forces resisting rotation.

7. A strap dispenser including in combination a reel plate on which a coil of mill wound strap is adapted to be laid, means mounting said plate for rotation, a stationary stripper mechanism positioned adjacent said reel plate and spaced axially therefrom a distance only slightly greater than the Width of the strap in the coil, a center disc secured to said reel plate and positioned between said reel plate and said stripper mechanism and about which strap is adapted toibe wound in ribbon wound coil form, and said stripper mechanism including means to guide the strap as it is withdrawn from a convolution adjacent the periphery of said center disc, whereby strap is wound around said center disc from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use, the withdrawal of strap from the center of the ribbon wound coil rotating said plate and the coils when the friction developed between the ribbon wound coil and said plate and said center disc is sufficient to overcome the forces resisting rotation.

8. A strap dispenser including in combination a reel plate on which a coil of mill wound strap is adapted to be laid, means mounting said plate for rotation, a stationary stripper mechanism positioned adjacent said reel plate and spaced axially therefrom a distance only slightly greater than the width of the strap in the coil, a center disc positioned between said reel plate and said stripper mechanism and about which strap is adapted to be wound in ribbon wound coil form, friction means between said reel plate and said center disc so that rotation of the latter will at least assist in driving the former, and said stripper mechanism including means-to guide the strap as it is withdrawn from a convolution adjacent the periphery of said centerdisc, whereby strap is wound around said center disc from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use, the withdrawal of strap. from the center of the ribbon wound coil rotating said plate and the coils when the friction developed between the ribbon wound coil and said plate and said center disc is sufficient to overcome the forces resisting rotation.

9. A strap dispenser including in combination a reel plate on which a coil of mill wound strapis adapted to be laid, means mounting said plate for rotation, a stationary stripper mechanism positioned adjacent said reel plate and spaced axially therefrom a distance only slightly greater than the width of thestrap'in'the coil, a center disc positioned between said reel plate and said stripper mechanism and about which strap is adapted to be wound in. ribbon wound coil form, drive means interconnecting said reel plate and said center disc, and said stripper mechanism including means to guide the strap as it is withdrawn'from a convolution adjacent the periphery of said center disc, whereby strapis wound around said center disc from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use, the withdrawal of strap from the center of the ribbon wound coil rotating said reel plate and the coils when the friction developed between the ribbon wound coil and said plate and said center disc is sufficient to overcome the forces resisting rotation.

10. A strap dispenser including in combination a reel adapted to support a coil of mill wound strap; means mounting said reel for rotation, a stationary stripper plate positioned adjacent said reel and spaced axially therefrom a distance only slightly greater than'the width of the strap in the coil, means on said reel and positioned between said reel and said stripper plate and about which strap is adapted to be wound from the center of the mill wound coil in ribbon wound coil form, said stripper plate having an arcuate recess in its peripheral edge through which the strap is withdrawn from a convolution adjacent said means about which a ribbon wound coil is formed, and guide means on said stripper plate at" said recess to guide strap'through said recess from. the center of the ribbon wound coil, whereby strap-is wound about said first named means from the center of the mill wound coil to form a ribbon wound coil from the center of which strap is pulled for use.

11. A strap dispenser including in combination a reel plate on which a coil of mill wound strap is adapted to be laid, means mounting said plate for rotation, at stationary stripper plate positioned adjacent said reel plate and spaced axially therefrom a distance onlyslightly greater than the width of the strap in the coil, a center disc rotatable about the axis of rotation of said reel plate and adapted to assist in rotating said reel plate positioried between said reel plate and said stripper, plate and about which strap is adapted tobe wound in ribbon wound coil form, and means on'said stripper plate to guide the strap as it is withdrawn from a convolution adjacent the periphery of the center disc, whereby strap is wound around said center disc from the center of the mill wound coil to form a ribbon Wound coil from the center of which strap is pulled for use, the resistance to slippage between the ribbon wound coil and said reel plate and said center disc determining'whether or not withdrawal of strap will rotate said reel plate and the Great Britain Oct. 22, 1952 

